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#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
const int NMAX = 200505;
int N, M;
vector<int> G[NMAX], GT[NMAX];
inline int notNode(int node) {
return node <= N ? node + N : node - N;
}
inline int nodeNotation(int node) {
return node < 0 ? -node + N : node;
}
void addEdge(int x, int y) {
G[x].push_back(y);
GT[y].push_back(x);
}
void addOrEdge(int x, int y) {
addEdge(notNode(x), y);
addEdge(notNode(y), x);
}
void read() {
scanf("%d%d", &N, &M);
int x, y;
for (int edgeIdx = 0; edgeIdx < M; edgeIdx++) {
scanf("%d%d", &x, &y);
x = nodeNotation(x); y = nodeNotation(y);
addOrEdge(x, y);
}
}
void dfsNormalGraph(int node, vector<bool>& visited, vector<int>& sortedByExitTime) {
visited[node] = true;
for (auto& neighbour : G[node]) {
if (!visited[neighbour]) {
dfsNormalGraph(neighbour, visited, sortedByExitTime);
}
}
sortedByExitTime.push_back(node);
}
void dfsTransposeGraph(int node, vector<int>& component, int componentIdx) {
component[node] = componentIdx;
for (auto& neighbour : GT[node]) {
if (component[neighbour] == -1) {
dfsTransposeGraph(neighbour, component, componentIdx);
}
}
}
void solve() {
vector<int> sortedByExitTime;
vector<bool> visited(2 * N + 1, false);
for (int node = 1; node <= 2 * N; node++) {
if (!visited[node]) {
dfsNormalGraph(node, visited, sortedByExitTime);
}
}
reverse(sortedByExitTime.begin(), sortedByExitTime.end());
vector<int> component(2 * N + 1, -1);
int componentIdx = 0;
for (auto& node : sortedByExitTime) {
if (component[node] == -1) {
dfsTransposeGraph(node, component, ++componentIdx);
}
}
for (int node = 1; node <= N; node++) {
if (component[node] == component[notNode(node)]) {
printf("-1\n");
return;
}
}
for (int node = 1; node <= N; node++) {
printf("%d ", component[node] > component[notNode(node)]);
}
printf("\n");
}
int main() {
freopen("2sat.in", "r", stdin);
freopen("2sat.out", "w", stdout);
read();
solve();
return 0;
}